Error: The number of HA heartbeat datastores for this host is 0, which is less than required: 2 observed.

Products

• VMware vSphere ESXi
• VMware vCenter Server
• VMware Telco Cloud Platform

Issue/Introduction

• Host summary page displays: "The number of vSphere HA heartbeat datastores for this host is 0, which is less than required: 2" observed in the vCenter GUI on a host in an vSphere High Availability enabled cluster."
  
  

Environment

• VMware vSphere ESXi 7.x
• VMware vSphere ESXi 8.x
• VMware vSphere ESXi 9.x
• TCP: 5.1

Cause

This alert triggers when lower than two shared datastores are designated or accessible for heartbeating. As of vSphere 6.0 and above, vSphere HA requires a minimum of two shared datastores accessible by all hosts within the cluster to handle datastore heartbeat monitoring.

• Log in to vCenter Server.
• Navigate to affected cluster > Configure > vSphere Availability.
• Expand Datastore for Heartbeating
• Verify that no datastores are configured

Confirm this by looking at the Heartbeat datastore configuration for the cluster in question and confirm that no datastores have been selected:

Resolution

To resolve this issue, add at least two heartbeat datastore for HA monitoring to the vSphere Availability configuration.

1. Log in to vCenter Server.
2. Navigate to affected cluster > Configure > vSphere Availability.
3. Click Edit for vSphere HA and navigate to Heartbeat Datastores
4. Pick either Automatically select datastores accessible from the hosts or Use datastores from the specified list and complement automatically if needed
5. If Use datastores from the specified list and complement automatically if needed is selected, then please select at least two datastores from the Available heartbeat datastores list below.

Then confirm the setting change.